如何將長字符串（帶有新行）變量作為環境傳遞給 ssh 命令

Question

KEY=$(cat ~/.ssh/id_rsa.pub)
ssh root@127.0.0.1 KEY="$KEY" echo "hi"

它將失敗並顯示如下錯誤：

bash: AAAAB3NzaC1yc2EAAAADAQABAAABAQDJ65FHdb8FyD...tpFnRUSZ: No such file or directory

我該如何解決？

Answer 1

假設使用 bash：

對於更通用的情況，輸入可能包含任意字符，包括引號，請考慮使用（特定於基本的） ${var@A}創建分配：

ssh root@localhost ${KEY@A} echo 'hi'

更新 1：bash（4.4 版）手冊頁：在“@A”（和其他）操作上：

 ${parameter@operator} Parameter transformation. The expansion is either a transformation of the value of parameter or information about parameter itself, depending on the value of operator. Each operator is a single letter: Q The expansion is a string that is the value of parameter quoted in a format that can be reused as input. E The expansion is a string that is the value of parameter with backslash escape sequences expanded as with the $'...' quoting mechansim. P The expansion is a string that is the result of expanding the value of parameter as if it were a prompt string (see PROMPTING below). A The expansion is a string in the form of an assignment statement or declare command that, if evaluated, will recreate parameter with its attributes and value. a The expansion is a string consisting of flag values representing parameter's attributes.